1. Field of the Invention
This invention relates to guide wires and catheters or the type used by the medical profession for infusion or medicaments to a tissue site within the body and to catheters of the type used to drain body fluids from tissue sites within the body, and more particularly relates to an improved steerable catheter that functions also as a guide wire and which can be navigated through tortuous pathways of small vasculatures for use in the treatment of and/or diagnostic evaluation of a target tissue site accessible through such small vasculatures and the tortuous pathways they present.
2. Description of the Prior Art
A preliminary palatability and novelty search in connection with this invention has revealed the existence of the following U.S. Pat. Nos.:
______________________________________ 1,790,244 4,068,660 4,368,730 4,377,169 4,471,779 4,490,421 4,534,363 4,545,390 4,548,206 4,554,929 4,573,470 4,586,923 4,601,705 4,613,385 4,616,653 4,619,263 4,641,654 4,646,719 4,646,742 4,676,249 4,708,717 4,719,924 4,715,378 4,717,387 4,721,117 4,723,936 4,739,768 4,763,647 4,767,400 4,779,628 4,798,598 4,832,047 4,846,186 4,899,787 4,906,241 4,925,445 4,953,553 5,021,044 5,041,085 5,059,851 5,107,852 5,165,421 5,176,661 5,178,158 5,184,627 5,195,971 5,209,727 5,211,636 5,250,034 5,267,979 5,306,252 5,345,945 5,462,523 5,569,197 5,571,085 5,591,142 5,606,981 5,611,777 ______________________________________
The steerable infusion catheter/guide wire forming the subject matter of the invention disclosed and claimed herein provides important improvements over current conventional prior art infusion catheters that, because of their design, require utilization or a separate prior-inserted guide wire to navigate a tortuous pathway to a specific tissue site within the body. Such conventional prior art infusion catheters possess limited mechanical and functional performance characteristics in terms of torqueability, penetration or "pushability", limited maneuverability and low bursting strengths. The unitary steerable infusion catheter/guide wire of the present invention obviates the enumerated limitations of conventional infusion catheters and conventional guide wires.
Accordingly, it is one of the important objects of the present invention to provide a unitary steerable infusion catheter/guide wire that obviates a separate guide wire, and which incorporates an infusion port assembly sealingly mounted on the catheter/guide wire manipulable to selectively and controllably rotate the catheter/guide wire unitary structure.
Another object of the invention is the provision of a unitary steerable infusion catheter/guide wire structure that incorporates a metallic cannula segment that is flexible over its entire length yet which possesses sufficient columnar strength to sustain the force that is necessary to effect penetration of the catheter/guide wire through small vasculatures.
A still further object of the invention is the provision of a unitary steerable infusion catheter/guide wire that possesses a bursting strength exceeding 250 psi.
Yet another object of the invention is the provision of a unitary steerable infusion catheter/guide wire that as a single unit can perform the functions of a separate catheter and a separate guide wire in cooperative association with an appropriate superimposed catheter.
A still further object of the invention is the provision of a unitary steerable infusion catheter/guide wire in sealing association with an infusion port assembly that in combination possess infusion capabilities for the delivery of therapeutic and/or diagnostic materials to an anatomical site, accessed via the general vasculature and advanced through lumens of less than 2 mm in diameter.
A still further object of the invention is the provision of a unitary steerable infusion catheter/guide wire structure which largely solves or avoids problems inherent with conventional prior art separate guide wire and infusion catheter assemblies.
Yet another important object of the invention is the provision of a unitary steerable infusion catheter/guide wire that incorporates a detachable infusion port assembly manipulable to sealingly engage the metallic cannula segment of the infusion catheter/guide wire to facilitate rotation of the catheter/guide wire to more easily enable navigation of the distal end of the catheter/guide wire to an anatomical site within the body and the infusion under pressure or a fluid or fluid-like medicament into the tissue at the site.
A still further object of the invention is the provision of a unitary steerable infusion catheter/guide wire structure incorporating a flexible distal end segment provided with a non-metallic enveloping sleeve that facilitates passage of the distal end segment through tortuous pathways of small vasculatures.
Yet another object of the invention is the provision of a unitary steerable infusion catheter/guide wire incorporating a flexible distal end segment including a pair of axially aligned interconnected transversely -flexible metallic coils incorporating means enabling selective flexure of the flexible distal end segment to define a curve having a selected radius and retention of the curve during navigation or the distal end segment through small vasculatures.
Still another object of the invention is the provision of a combined-function steerable infusion catheter/guide wire structure incorporating a distal end segment enabling dispersion of fluid or fluid like medicaments axially and transversely of the longitudinal axis of the catheter.
A still further object of the invention is the provision of a unitary steerable infusion cathether/guide wire structure which, when used to function as a guide wire for a superimposed catheter, may be coated with a lubricious layer of friction-reducing material such as a silicon-based lubricant or a hydrophilic layer to facilitate superimposition of a catheter over the flexible yet steerable infusion catheter/guide wire structure.
Yet another object of the invention is the provision of a unitary structure that may selectively function as both a steerable infusion catheter/guide wire structure and/or a hollow guide wire, and which may be coated with a selected thrombolitic agent or agents, such as heparin, to minimize the possibility of thrombus formation during use in a procedure.
The invention possesses other objects and features of advantage, some of which, with the foregoing, will become apparent from the following description and the drawings. It is to be understood however that the invention is not limited to the embodiment illustrated and described since it may be embodied in various forms within the scope of the appended claims.